Indoor unit of air-conditioning apparatus and air-conditioning apparatus

ABSTRACT

An indoor unit includes: a casing formed with a suction port and a blow-out port; a plurality of fans provided in parallel in the casing; a heat exchanger provided on the downstream side of the fans and on the upstream side of the blow-out port; a horizontal wind direction control vane provided at the blow-out port to control the horizontal direction of an airflow blown out from the blow-out port; a vertical wind direction control vane provided at the blow-out port to control the vertical direction of the airflow blown out from the blow-out port; and an infrared ray human detection sensor configured to detect the position of a person present in a room, and air volumes, the orientation of the horizontal wind direction control vane, and the orientation of the vertical wind direction control vane of the fans are each controlled according to results of detection by the infrared ray sensor.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an indoor unit having a fan and a heatexchanger housed in a casing and an air-conditioning apparatus havingthe indoor unit.

2. Description of the Related Art

Conventionally, an air-conditioning apparatus (more specifically, anindoor unit) having a vertical wind direction control vane divided intothree parts and a horizontal wind direction control vane and configuredto control the direction of an airflow blown out from a blow-out portusing the vertical wind direction control vane divided into three partsand the horizontal wind direction control vane has been proposed. Morespecifically, two parts of the vertical wind direction control vaneother than the central part are controlled in the closing direction ofthe blow-out port and the horizontal wind direction control vane iscontrolled to throttle the airflow blown out from the blow-out port, sothat the velocity of the airflow blown out from the center of theblow-out port is increased. Accordingly, people present in a room areprovided with more comfort (for example, see Japanese Unexamined PatentApplication Publication No. 2001-153428).

The conventional air-conditioning apparatus controls the direction ofthe airflow blown out from the blow-out port using only the verticalwind direction control vane divided into three parts and the horizontalwind direction control vane. Therefore, distribution of airflowsdifferent in air volume individually to different places in the roomwere unfortunately not possible.

SUMMARY OF THE INVENTION

In order to solve the above-described problem, it is an object of theinvention to provide an indoor unit of an air-conditioning apparatus,which is capable of distributing airflows different in air volumeindividually to different places in a room, and an air-conditioningapparatus having such an indoor unit.

An indoor unit of an air-conditioning apparatus according to theinvention includes: a casing having a suction port formed on an upperportion and a blow-out port formed on a lower side of a front surfaceportion; a plurality of axial-flow or mixed-flow fans provided inparallel on the downstream side of the suction port in the casing; aheat exchanger provided on the downstream side of each fans and on theupstream side of each blow-out port in the casing and configured toexchange heat between air blown out from the fan and a refrigerant; ahorizontal wind direction control vane provided at the blow-out port andconfigured to control the horizontal direction of an airflow blown outfrom the blow-out port; a vertical wind direction control vane providedat the blow-out port and configured to control the vertical direction ofthe airflow blown out from the blow-out port; and a human detectionsensor configured to detect the position of a person present in a room,in which the air volume, the orientation of the horizontal winddirection control vane, and the orientation of the vertical winddirection control vane of each of the fans are each controlled accordingto detected results of the human detection sensor.

The air-conditioning apparatus according to the invention includes theindoor unit described above.

According to the invention, the situation in the room (for example,where a person is present) can be detected by the human detectionsensor. Then, by controlling the air volume, the orientation of thehorizontal wind direction control vane, and the orientation of thevertical wind direction control vane of each of the fans according todetected results of the human detection sensor, airflows of differentair volumes can be distributed individually to different places in theroom. Controlling each air volume of the fans does not mean to differeach of the air volumes of each fans. As a matter of course, the airvolumes of some fans may be the same.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a vertical cross-sectional view illustrating an indoor unit ofan air-conditioning apparatus according to Embodiment 1 of theinvention.

FIG. 2 is a perspective view illustrating the indoor unit of theair-conditioning apparatus according to Embodiment 1 of the invention.

FIG. 3 is a front cross-sectional view illustrating the indoor unitaccording to Embodiment 1 of the invention.

FIG. 4 is a perspective view illustrating the indoor unit according toEmbodiment 1 of the invention.

FIG. 5 is an explanatory drawing illustrating each light distributionview angles of light-receiving elements in an infrared ray sensoraccording to Embodiment 1 of the invention.

FIG. 6 is a perspective view illustrating a housing for accommodatingthe infrared ray sensor according to Embodiment 1 of the invention.

FIG. 7A is an explanatory drawing illustrating a turning state of theinfrared ray sensor according to Embodiment 1 of the invention.

FIG. 7B is an explanatory drawing illustrating another turning state ofthe infrared ray sensor according to Embodiment 1 of the invention.

FIG. 7C is an explanatory drawing illustrating still another turningstate of the infrared ray sensor according to Embodiment 1 of theinvention.

FIG. 8 is an explanatory drawing illustrating vertical lightdistribution view angles in a vertical cross section of the infrared raysensor according to Embodiment 1 of the invention.

FIG. 9 shows an example of heat image data obtained by the infrared raysensor according to Embodiment 1.

FIG. 10 shows an example in which the indoor unit according toEmbodiment 1 divides a floor surface area in a room into a plurality ofarea blocks.

FIG. 11 is a front cross-sectional view illustrating the indoor unitaccording to Embodiment 2 of the invention.

FIG. 12 is a perspective view illustrating the indoor unit according toEmbodiment 2 of the invention.

FIG. 13 is a front cross-sectional view illustrating the indoor unitaccording to Embodiment 3 of the invention.

FIG. 14 is a perspective view illustrating the indoor unit according toEmbodiment 3 of the invention.

FIG. 15 is a perspective view of the indoor unit according to Embodiment1 of the invention when viewed from the front right side.

FIG. 16 is a perspective view of the indoor unit according to Embodiment1 of the invention when viewed from the rear right side.

FIG. 17 is a perspective view of the indoor unit according to Embodiment1 of the invention when viewed from the front left side.

FIG. 18 is a perspective view illustrating a drain pan according toEmbodiment 1 of the invention.

FIG. 19 is a vertical cross-sectional view illustrating a dewcondensation forming position of the indoor unit according to Embodiment1 of the invention.

FIG. 20 is a configuration drawing illustrating a signal processingdevice according to Embodiment 1 of the invention.

FIG. 21 is a vertical cross-sectional view illustrating another exampleof the indoor unit of the air-conditioning apparatus according toEmbodiment 1 of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, detailed embodiments of an air-conditioning apparatusaccording to the invention (more specifically, an indoor unit of theair-conditioning apparatus) will be described. In the followingembodiments, the invention will be described with a wall indoor unittaken as an example. In the drawings showing respective embodiments,part of the shapes or the sizes of each units (or the components of eachunits) may be different.

Embodiment 1 <Basic Configuration>

FIG. 1 is a vertical cross-sectional view illustrating an indoor unit(referred to as “indoor unit 100”) of an air-conditioning apparatusaccording to Embodiment 1 of the invention. FIG. 2 is a perspective viewillustrating the indoor unit shown in FIG. 1. In the description ofEmbodiment 1 and other embodiments described later, the left side inFIG. 1 is defined as the front side of the indoor unit 100. Referringnow to FIG. 1 and FIG. 2, a configuration of the indoor unit 100 will bedescribed.

(General Configuration)

The indoor unit 100 supplies air-conditioned air to an area to beair-conditioned such as an indoor space by utilizing a refrigeratingcycle circulating a refrigerant. The indoor unit 100 mainly includes acasing 1 formed with suction ports 2 for taking in indoor air and ablow-out port 3 for supplying air-conditioned air to the area to beair-conditioned, fans 20 housed in the casing 1 and configured to takein the indoor air from the suction ports 2 and blow out theair-conditioned air from the blow-out port 3, and heat exchangers 50disposed in air paths from the fans 20 to the blow-out port 3 andconfigured to generate the air-conditioned air by heat exchange betweenthe refrigerant and the indoor air. In these components, each of the airpaths (an arrow Z in FIG. 1) communicates with the interior of thecasing 1. The suction ports 2 are formed so as to open at an upperportion of the casing 1. The blow-out port 3 is formed so as to open ata lower portion of the casing 1 (more specifically, on the lower side ofa front surface portion of the casing 1). The fans 20 are each disposedon the downstream side of the suction ports 2 and the upstream side ofthe heat exchangers 50, and, for example, axial-flow fans or mixed-flowfans are employed.

The indoor unit 100 is provided with a control device 281 configured tocontrol the rotation speeds of the fans 20, the orientations (angles) ofa later described vertical wind direction control vane 70 and ahorizontal wind direction control vane 80 (if an auxiliary vertical winddirection control vane 71, described later, is provided, the auxiliaryvertical wind direction control vane 71 is also included), and so on. Insome cases, illustration of the control device 281 may be omitted indrawings illustrating Embodiment 1 and other embodiments describedlater.

Since the fans 20 are provided on the upstream side of the heatexchangers 50 in the indoor unit 100 as configured above, generation ofa swirl flow of air blown out from the blow-out port 3 and occurrence ofvariation in wind velocity distribution can be restrained in comparisonwith the indoor unit of the conventional air-conditioning apparatushaving the fan 20 at the blow-out port 3. Therefore, blowing ofcomfortable air to the area to be air-conditioned is achieved. Since nocomplex structure such as a fan is provided at the blow-out port 3,measures against dew condensation formed at a boundary between warm airand cool air at the time of a cooling operation can easily beimplemented. In addition, since a fan motor 30 is not exposed toair-conditioned air, namely, cool air or warm air, a long operationallife can be provided.

(Fan)

In general, the indoor unit of the air-conditioning apparatus haslimitations in terms of installation space, so the fan cannot beincreased in size in many cases. Therefore, in order to obtain a desiredair volume, a plurality of fans of moderate sizes are arranged inparallel. In the indoor unit 100 according to Embodiment 1, three fans20 are arranged in parallel along the longitudinal direction of thecasing 1 (that is, along the longitudinal direction of the blow-out port3) as shown in FIG. 2. In order to obtain a desired heat-exchangecapacity with the indoor unit of the air-conditioning apparatus havingtypical dimensions, three to four fans 20 are preferably provided. Inthe indoor unit according to Embodiment 1, substantially equivalent airvolumes can be obtained from all of the fans 20 by configuring all ofthe fans 20 to have an identical shape and so as to operate all with thesame rotation speed.

In this configuration, by combining the number, the shape, and the sizeof the fans 20 according to the required air volume and the air-flowresistance in the interior of the indoor unit 100, an optimal fan designfor the indoor units 100 having various specifications is achieved.

(Bell Mouth)

In the indoor unit 100 according to Embodiment 1, a duct-like bell mouth5 is arranged around each of the fans 20. The bell mouth 5 is intendedto guide intake air into and exhaust air out of the fans smoothly. Asshown in FIG. 2, for example, the bell mouth 5 according to Embodiment 1has a substantially circular shape in plan view. In the vertical crosssection, the bell mouth 5 according to Embodiment 1 has the followingshape. An end portion of an upper portion 5 a has a substantiallycircular arc shape extending outward and upward. A center portion 5 b isa straight portion of the bell mouth 5, having a constant diameter. Anend portion of a lower portion 5 c has a substantially circular arcshape extending outward and downward. An end portion (a circular arcportion on the suction side) of the upper portion 5 a of the bell mouth5 forms the suction port 2.

The bell mouth 5 may be formed integrally with, for example, the casing1 in order to reduce the number of components and improve the strength.It is also possible, for example, to improve maintainability bymodularizing the bell mouth 5, the fan 20, and the fan motor 30 so as tobe detachably attachable to the casing 1.

In Embodiment 1, the end portion (the circular arc portion on thesuction side) of the upper portion 5 a of the bell mouth 5 is formed soas to have a uniform shape in terms of the circumferential direction ofan opening surface of the bell mouth 5. In other words, the bell mouth 5does not have structures such as a notch or a rib in the direction ofrotation about an axis of rotation 20 a of the fan 20, and has a uniformshape in terms of axial symmetry.

With the configuration of the bell mouth 5 as described above, the endportion (the circular arc portion on the suction side) of the upperportion 5 a of the bell mouth 5 has a uniform shape with respect to therotation of the fan 20, and hence a uniform flow of the suction flow ofthe fan 20 is also realized. Therefore, the noise generated by a driftof the suction flow of the fan 20 can be decreased.

(Partitioning Panel)

As shown in FIG. 2, the indoor unit 100 according to Embodiment 1 isprovided with partitioning panels 90 between the adjacent fans 20. Thesepartitioning panels 90 are installed between the heat exchangers 50 andthe fans 20. In other words, the air paths between the heat exchangers50 and the fans 20 are divided into a plurality of air paths (three inEmbodiment 1). The partitioning panels 90 are arranged between the heatexchangers 50 and the fans 20, so each end portion that is in contactwith the heat exchanger 50 has a shape conforming to the shape of theheat exchanger 50. More specifically, as shown in FIG. 1, the heatexchanger 50 is arranged so as to form a substantially A-shape in avertical cross section from the front side to the back side of theindoor unit 100 (that is, the vertical cross section when viewing theindoor unit 100 from the right side, referred to as “right verticalcross-section”, hereinafter). Therefore, an end portion of each of thepartitioning panels 90 on the side of the heat exchanger 50 also has asubstantially A-shape.

The position of an end portion of each of the partitioning panels 90 onthe side of the fan 20 may be determined as follows, for example. Whenthe adjacent fans 20 are positioned sufficiently away from each other toavoid influencing each other on the suction side, the end portion ofeach of the partitioning panels 90 on the side of the fan 20 may needonly be extend to an exit surface of the fan 20. However, in a casewhere the adjacent fans 20 are as near to each other to influence eachother on the suction side and, in addition, in a case where the shape ofthe end portion (the circular arc portion on the suction side) of theupper portion 5 a of the bell mouth 5 can be formed sufficiently large,the end portion of each of the partitioning panels 90 on the side of thefan 20 may extend up to the upstream side of the fan 20 (the suctionside) so that the adjacent air paths do not influence each other (theadjacent fans 20 do not influence each other on the suction side).

The partitioning panels 90 may be formed of various materials. Forexample, the partitioning panels 90 may be formed of a metal such assteel or aluminum. Also, for example, the partitioning panels 90 may beformed of a resin. When the partitioning panels 90 are formed of amaterial with a low melting point such as a resin, however, since theheat exchangers 50 are heated to high temperatures at the time of aheating operation, formation of slight spaces between the partitioningpanels 90 and the heat exchangers 50 is recommended. When thepartitioning panels 90 are formed of a material with a high meltingpoint such as aluminum or steel, the partitioning panels 90 may bearranged so as to be in contact with the respective heat exchangers 50.If the heat exchangers 50 are, for example, fin and tube heatexchangers, the partitioning panels 90 may be inserted between the finsof the heat exchangers 50.

As described above, the air path between the heat exchangers 50 and thefans 20 is divided into a plurality of air paths (three in Embodiment1). It is also possible to reduce the noise generated in the ducts byproviding sound-absorbing materials in these air paths, that is, on thepartitioning panels 90 or in the casing 1.

The divided air paths are each formed into a substantially square shapeof L1×L2. In other words, the widths of the divided air paths are L1 andL2. Therefore, the air volume generated by the fan 20 installed in theinterior of the substantially square shape of L1×L2, for example,reliably passes through the heat exchanger 50 surrounded by an areadefined by L1 and L2 on the downstream side of the fan 20.

By dividing the air path in the casing 1 into the plurality of air pathsas described above, even when the flow field which is generated by thefan 20 on the downstream side has a swirling component, air blown outfrom each of the fans 20 is prevented from moving freely in thelongitudinal direction of the indoor unit 100 (the direction orthogonalto the plane of the paper of FIG. 1). Therefore, the air blown out fromthe fan 20 can be made to pass through the heat exchanger 50 in the areadefined by L1 and L2 on the downstream side of the fan 20. Consequently,variations in air volume distribution of the air flowing into all theheat exchangers 50 in the longitudinal direction of the indoor unit 100(the direction orthogonal to the plane of the paper of FIG. 1) isrestrained, so that a high heat exchanging capacity can be provided.Furthermore, by partitioning the interior of the casing 1 by using thepartitioning panels 90, the mutual interference of the swirl flowsgenerated by the adjacent fans 20 can be prevented between the fans 20adjacent to each other. Therefore, an energy loss of fluid due to themutual interference of the swirl flows can be prevented, and hencereduction of a pressure loss in the indoor unit 100 is possible inaddition to the improvement in the wind velocity distribution. Each ofthe partitioning panels 90 does not necessarily have to be formed of asingle plate, and may be made up of a plurality of plates. For example,the partitioning panel 90 may be divided into two parts on the side of afront heat exchanger 51 and on the side of a back side heat exchanger55. Needless to say, it is preferable that no gap be formed at a jointportion between the respective plates which constitute the partitioningpanel 90. By dividing the partitioning panel 90 into a plurality ofplates, assemblability of the partitioning panels 90 is improved.

(Fan Motor)

The fan 20 is driven and rotated by the fan motor 30. The fan motor 30to be used may be either of an inner-rotor type or an outer-rotor type.In the case of the fan motor 30 of the outer-rotor type, a motor havinga structure in which a rotor is integrated with a boss 21 of the fan 20(the rotor is held by the boss 21) is also employed. By setting thedimensions of the fan motor 30 to be smaller than the dimensions of theboss 21 of the fan 20, loss of airflow generated by the fan 20 can beprevented. In addition, by disposing the motor in the interior of theboss 21, an axial dimension can also be reduced. With the easilydetachable and attachable structure of the fan motor 30 and the fan 20,cleanability is also improved.

By using a Brushless DC motor which is relatively high in cost as thefan motor 30, improvement in efficiency, elongation of service life, andimprovement in controllability are achieved. Needless to say, however, aprimary function of an air-conditioning apparatus is achieved even whenmotors of other types are employed.

A circuit for driving the fan motor 30 may be integrated with the fanmotor 30, or may be provided externally for dust-proofing measures andfire prevention measures.

The fan motor 30 is attached to the casing 1 using a motor stay 16. Inaddition, by configuring the fan motor 30 to be of a box-type fan motor(in which the fan 20, a housing, and the fan motor 30 are integrallymodularized) used for cooling a CPU and configuring the fan motor 30 soas to be detachably attached to the motor stay 16, maintainability canbe improved, and accuracy of tip clearance of the fan 20 can also beimproved.

A drive circuit of the fan motor 30 may be provided either in theinterior of or on the exterior of the fan motor 30.

(Motor Stay)

The motor stay 16 is provided with a fixing member 17 and supportingmembers 18. The fixing member 17 is a member to which the fan motor 30is attached. The supporting members 18 are members configured to fix thefixing member 17 to the casing 1. The supporting members 18 are, forexample, rod-shaped members, and extend, for example, radially from anouter peripheral portion of the fixing member 17. As shown in FIG. 1,the supporting members 18 according to Embodiment 1 are extendapproximately horizontally.

(Heat Exchanger)

The heat exchangers 50 of the indoor unit 100 according to Embodiment 1are arranged on the downstream sides of the fans 20. Fin and tube heatexchangers are preferably used as the heat exchangers 50. The heatexchangers 50 are each divided by a line of symmetry 50 a in the rightvertical cross section as shown in FIG. 1. The line of symmetry 50 adivides the area substantially in the center in the horizontal directionof which the heat exchanger 50 is installed in this cross section. Inother words, the front side heat exchanger 51 is arranged on the frontside (the left side in the plane of the paper in FIG. 1) with respect tothe line of symmetry 50 a and the back side heat exchanger 55 isarranged on the back side (the right side in the plane of the paper inFIG. 1) with respect to the line of symmetry 50 a, respectively. Thefront side heat exchanger 51 and the back side heat exchanger 55 arearranged in the casing 1 so that the distance between the front sideheat exchanger 51 and the back side heat exchanger 55 increases in thedirection of an air current, that is, so that the cross-sectional shapeof the heat exchanger 50 forms a substantially inverted V-shape in theright vertical cross section. In other words, the front side heatexchanger 51 and the back side heat exchanger 55 are arranged so as tobe inclined with respect to the direction of the air current suppliedfrom the fan 20.

In addition, the heat exchanger 50 is characterized in that the air patharea of the back side heat exchanger 55 is larger than the air path areaof the front side heat exchanger 51. In other words, the heat exchanger50 is arranged so that the air volume of the back side heat exchanger 55is larger than the air volume of the front side heat exchanger 51. InEmbodiment 1, the length of the back side heat exchanger 55 in thelongitudinal direction is larger than the length of the front side heatexchanger 51 in the longitudinal direction in the right vertical crosssection. Accordingly, the air path area of the back side heat exchanger55 is larger than the air path area of the front side heat exchanger 51.The rest of the configuration (such as the lengths in the depthdirection in FIG. 1) of the front side heat exchanger 51 and that of theback side heat exchanger 55 are the same. In other words, the heatconduction area of the back side heat exchanger 55 is larger than theheat conduction area of the front side heat exchanger 51. Also, the axisof rotation 20 a of the fan 20 is arranged above the line of symmetry 50a.

With the configuration of the heat exchanger 50 as described above, thegeneration of the swirl flow of the air blown out from the blow-out port3 and the occurrence of a variation in wind velocity distribution can berestrained in comparison with the indoor unit of the conventionalair-conditioning apparatus having the fan at the blow-out port. Also,with the configuration of the heat exchanger 50 as described above, theair volume of the back side heat exchanger 55 is larger than the airvolume of the front side heat exchanger 51. Because of this differencein air volume, when air currents having passed through the front sideheat exchanger 51 and the back side heat exchanger 55 merge, the mergedair current is curved toward the front side (the side of the blow-outport 3). Therefore, necessity to curve the airflow steeply in thevicinity of the blow-out port 3 is eliminated, and hence the pressureloss in the vicinity of the blow-out port 3 can be reduced.

In the indoor unit 100 according to Embodiment 1, the air currentflowing out from the back side heat exchanger 55 flows in the directionfrom the back side to the front side. Therefore, in the indoor unit 100according to Embodiment 1, the air current after having passed the heatexchanger 50 can be curved more easily than in the case where the heatexchanger 50 is arranged in a substantially V-shape in the rightvertical cross section.

The indoor unit 100 includes the plurality of fans 20, which oftenresults in an increase in weight. When the weight of the indoor unit 100increases, a wall surface strong enough for installing the indoor unit100 is required, which leads to a restriction of installation.Therefore, reduction of weight of the heat exchanger 50 is preferred. Inaddition, in the indoor unit 100, since the fans 20 are arranged on theupstream sides of the heat exchangers 50, the height of the indoor unit100 is increased, which often leads to a restriction of installation.Therefore, downsizing of the heat exchanger 50 is preferred.

Accordingly, in Embodiment 1, the fin and tube heat exchanger isemployed as the heat exchanger 50 (the front side heat exchanger 51 andthe back side heat exchanger 55) to achieve downsize of the heatexchanger 50. More specifically, the heat exchanger 50 according toEmbodiment 1 includes a plurality of fins 56 arranged side by side withpredetermined gaps therebetween and a plurality of heat-transfer tubes57 penetrating through the fins 56. In Embodiment 1, the fins 56 arearranged side by side in the horizontal direction of the casing 1 (thedirection orthogonal to the plane of the paper of FIG. 1). In otherwords, the heat-transfer tubes 57 penetrate through the fins 56 alongthe horizontal direction of the casing 1 (the direction orthogonal tothe plane of the paper of FIG. 1). In Embodiment 1, in order to improveheat-transfer efficiency of the heat exchanger 50, two rows of theheat-transfer tubes 57 are arranged in the direction of air flow of theheat exchanger 50 (the width direction of the fins 56). Theheat-transfer tubes 57 are arranged in a substantially zigzag shape inright vertical cross section.

Downsizing of the heat exchanger 50 is achieved by configuring theheat-transfer tubes 57 with circular tubes having a small diameter (onthe order of diameters ranging from 3 mm to 7 mm), and employing R32 asthe refrigerant flowing through the heat-transfer tubes 57 (therefrigerant used in the indoor unit 100 and in the air-conditioningapparatus having the indoor unit 100). In other words, the heatexchanger 50 exchanges heat between the refrigerant flowing in theinteriors of the heat-transfer tubes 57 and the indoor air via the fins56. Therefore, when the diameter of the heat-transfer tubes 57 isreduced, with the same amount of circulation of the refrigerant, thepressure loss of the refrigerant is larger than that of the heatexchanger provided with heat-transfer tubes having a large diameter.However, the latent heat of evaporation of R32 is higher than that ofR410A at the same temperature, and hence the same capacity can beobtained with a smaller amount of circulation of the refrigerant.Therefore, by using R32, reduction of the amount of a refrigerant to beused is made possible, and the pressure loss in the heat exchanger 50can be reduced. Therefore, by employing thin circular tubes as theheat-transfer tubes 57, and using R32 as the refrigerant, downsizing ofthe heat exchanger 50 is achieved.

Furthermore, in the heat exchanger 50 according to Embodiment 1, areduction in the weight of the heat exchanger 50 is achieved by formingthe fins 56 and the heat-transfer tubes 57 with aluminum or aluminumalloy. And if the weight of the heat exchanger 50 does not cause arestriction of installation, the heat-transfer tubes 57 may be formed ofcopper as a matter of course.

(Finger Guard and Filter)

The indoor unit 100 according to Embodiment 1, a finger guard 15 and afilter 10 are provided at the suction port 2. The finger guard 15 isinstalled for the purpose of preventing the rotating fan 20 from beingtouched. Therefore, the shape of the finger guard 15 is arbitrary aslong as the fan 20 is prevented from being touched. For example, theshape of the finger guard 15 may be a lattice shape, or may be acircular shape made up of a number of rings having different sizes.Alternatively, the finger guard 15 may be formed either of materialssuch as resin or metallic materials, However, when strength is required,it is preferably formed of metal. The finger guard 15 is preferablyformed of materials and shapes as strong and thin as possible in termsof reduction of air-flow resistance and retention of strength. Thefilter 10 is provided for the purpose of preventing dust from flowinginto the interior of the indoor unit 100. The filter 10 is provided inthe casing 1 so as be detachable and attachable. The indoor unit 100according to Embodiment 1 includes an automatic cleaning mechanism whichcleans the filter 10 automatically.

(Wind Direction Control Vane)

The indoor unit 100 according to Embodiment 1 includes a vertical winddirection control vane 70 and a horizontal wind direction control vane80, which are mechanisms for controlling the blowing direction of theairflow, at the blow-out port 3. In Embodiment 1, the vertical winddirection control vane 70 and the horizontal wind direction control vane80 are controlled together with the air volumes of each fans 20 on thebasis of detected results of the human detection sensor. Accordingly,airflow controllability of the indoor unit 100 can be improved.

FIG. 3 is a front cross-sectional view illustrating the indoor unitaccording to Embodiment 1 of the invention. FIG. 4 is a perspective viewillustrating the same indoor unit. FIG. 3 is a front cross-sectionalview taken along the substantially center portions of the fans 20. Theindoor unit 100 shown in FIG. 3 and FIG. 4 show the indoor unit 100having the three fans 20 (fan 20A to fan 20C).

The horizontal wind direction control vane 80 is coupled to a motor 81,such as a stepping motor, via a link rod 82. By the motor 81 drivenaccording to the number of steps commanded by the control device 281,the orientation (angle) of the horizontal wind direction control vane 80is changed and the direction of airflow blown out from the blow-out port3 can be controlled in the horizontal direction. The vertical winddirection control vane 70 is coupled to a motor (not shown) such as astepping motor. By this motor driven according to the number of stepscommanded by the control device 281, the orientation (angle) of thevertical wind direction control vane 70 is changed and the direction ofairflow blown out from the blow-out port 3 can be controlled in thevertical direction.

In the indoor unit 100 according to Embodiment 1, a human detectionsensor configured to detect the position of a person present in a roomis provided. As a human detection sensor, various types such as a humandetection sensor using a camera may be used. In Embodiment 1, aninfrared ray sensor 410 is used as the human detection sensor. Theinfrared ray sensor 410 is configured to scan the area of the roomsubject to the detection of temperature and detect the temperature ofthe area of the room subject to the detection of temperature, and detectthe presence of a person, a heat generating equipment, or the like.

The infrared ray sensor 410 is provided on the lower portion of a frontsurface of the casing 1 above the blow-out port 3. The infrared raysensor 410 is rotatable in the horizontal direction, and is attached soas to face downward at a depression angle of approximately 24.5 degrees.Here, the depression angle means an angle of a center axis of theinfrared ray sensor 410 with respect to a horizontal line. In otherwords, the infrared ray sensor 410 is attached so as to face downward atan angle of approximately 24.5 degrees with respect to the horizontalline.

FIG. 5 is an explanatory drawing illustrating each light distributionview angles of a light-receiving element in the infrared ray sensoraccording to Embodiment 1 of the invention.

As shown in FIG. 5, the infrared ray sensor 410 includes eightlight-receiving elements (not shown) arranged in a line in the verticaldirection in a metallic container 411. Provided on an upper surface ofthe metallic container 411 is a window (not shown) formed of a lens forallowing infrared rays to pass through to the eight light-receivingelements. Light distribution view angles 412 of each light-receivingelements are 7 degrees in the vertical direction and 8 degrees in thehorizontal direction. Although the configuration in which the lightdistribution view angles 412 of each light-receiving elements are 7degrees in the vertical direction and 8 degrees in the horizontaldirection is shown in Embodiment 1, the light distribution view angles412 are not limited to these values (7 degrees in the vertical directionand 8 degrees in the horizontal direction). The number of thelight-receiving elements can be changed according to the lightdistribution view angles 412 of each light-receiving elements. Forexample, the light distribution view angles may be determined so thatthe product of vertical light distribution view angles of a singlelight-receiving element and the number of light-receiving elementsbecome constant.

FIG. 6 is a perspective view illustrating the housing for accommodatingthe infrared ray sensor according to Embodiment 1 of the invention. FIG.6 is a perspective view of a portion near the infrared ray sensor 410viewed from the back side (from inside the casing 1).

As shown in FIG. 6, the infrared ray sensor 410 is housed in theinterior of a housing 413. Provided above the housing 413 is a motor 414configured to drive the infrared ray sensor 410 (more specifically, torotate the infrared ray sensor 410 in the horizontal direction). Themotor 414 is, for example, a stepping motor. Mounting portions 415formed integrally with the housing 413 are fixed to the lower portion ofthe front surface of the casing 1, so that the infrared ray sensor 410is attached to the casing 1. In a state in which the infrared ray sensor410 is attached to the casing 1, the motor 414 and the housing 413 aresubstantially vertical. Subsequently, the infrared ray sensor 410 isattached to the interior of the housing 413 so as to face downward at adepression angle of approximately 24.5 degrees.

The infrared ray sensor 410 is driven by the motor 414 so as to rotatewithin a predetermined angular range in the horizontal direction (therotary drive like this is referred to as “turn”, here). Morespecifically, the infrared ray sensor 410 is turned as shown in FIGS. 7Ato 7C.

FIG. 7A is an explanatory drawing illustrating a turning state of theinfrared ray sensor according to Embodiment 1 of the invention, FIG. 7Bis an explanatory drawing illustrating another turning state of theinfrared ray sensor according to Embodiment 1 of the invention, and FIG.7C is an explanatory drawing illustrating still another turning state ofthe infrared ray sensor according to Embodiment 1 of the invention. FIG.7A, here, is a perspective view illustrating a state in which theinfrared ray sensor is turned to the left end (the right end in a stateof viewing indoors from inside the indoor unit 100). FIG. 7B is aperspective view illustrating a state in which the infrared ray sensoris turned to a center portion. FIG. 7C is a perspective viewillustrating a state in which the infrared ray sensor is turned to theright end (the left end in the state of viewing indoors from inside theindoor unit 100).

The infrared ray sensor 410 is turned from the left end (FIG. 7A)through the center portion (FIG. 7B) to the right end (FIG. 7C), andwhen it reaches the right end (FIG. 7C), it is inverted in direction andturns in the reverse direction. By repeating actions as described above,the infrared ray sensor 410 detects the temperature of the area subjectto the detection of temperature while scanning the area of the roomsubject to the detection of temperature in the horizontal direction.

Here, a method of acquiring heat image data of a wall, a floor, or thelike of a room using the infrared ray sensor 410 will be described.Control of the infrared ray sensor 410 and the like is performed by thecontrol device 281 in which predetermined actions are programmed (forexample, a microcomputer). In the following description, the expression“performed by the control device 281” for each control is omitted.

When acquiring the heat image data such as the wall, the floor, or thelike of a room, the infrared ray sensor 410 is turned in the horizontaldirection by the motor 414, and the infrared ray sensor 410 is stoppedfor a predetermined period (0.1 to 0.2 seconds) at each position atevery 1.6 degree of turning angle of the motor 414 (the angle of rotarydrive of the infrared ray sensor 410). After every stop of the infraredray sensor 410 at each position, the infrared ray sensor 410 is heldas-is for a predetermined period (a period shorter than 0.1 to 0.2seconds) to acquire the results of detection (heat image data) of theeight light-receiving elements of the infrared ray sensor 410. Afterhaving acquired the results of detection of the infrared ray sensor 410,the motor 414 is driven (at a turning angle of 1.6 degrees) again andthen is stopped, and the results of detection (heat image data) of theeight light-receiving elements of the infrared ray sensor 410 areacquired with the same actions.

The above-described operation is performed repeatedly, and the heatimage data in a detecting area are calculated on the basis of theresults of detection of the infrared ray sensor 410 at 94 points in thehorizontal direction. Since the heat image data is acquired by stoppingthe infrared ray sensor 410 at 94 points at every 1.6 degrees of turningangle of the motor 414, the turning range of the infrared ray sensor 410in the horizontal direction (the angular range of rotary drive in thehorizontal direction) is approximately 150.4 degrees.

FIG. 8 is an explanatory drawing illustrating the vertical lightdistribution view angles in a vertical cross section of the infrared raysensor according to Embodiment 1 of the invention. FIG. 8 shows thevertical light distribution view angles in the vertical cross section ofthe infrared ray sensor 410 having the eight light-receiving elementsarranged in a row in the vertical direction, in a state in which theindoor unit 100 is installed at a height of 1800 mm from the floorsurface of the room. The angle 7 degrees shown in FIG. 8 is the verticallight distribution view angle of a single light-receiving element.

The angle of 37.5 degrees in FIG. 8 shows an area out of the verticalview angle area of the infrared ray sensor 410 (an angle from the wallon which the indoor unit 100 is attached). If the depression angle ofthe infrared ray sensor 410 is 0 degree, this angle is 90 degrees−4 (thenumber of light-receiving elements positioned below the horizontalline)×7 degrees (the vertical light distribution view angle of a singlelight-receiving element)=62 degrees, since the depression angle of theinfrared ray sensor 410 according to Embodiment 1 is 24.5 degrees, thisangle is 62 degrees−24.5 degrees=37.5 degrees.

By using the infrared ray sensor 410 configured as above, the heat imagedata as shown below, for example, may be acquired.

FIG. 9 shows an example of the heat image data acquired by the infraredray sensor according to Embodiment 1. FIG. 9 shows a result obtained bycalculating the heat image data on the basis of the results of detectionacquired while causing the infrared ray sensor 410 to turn in thehorizontal direction in a daily instance in which a housewife 416 holdsan infant 417 in her arms in a room measuring eight tatami mats (13.2square meters).

FIG. 9 shows a heat image data acquired on a cloudy day in winter.Therefore, the temperature of a window 418 is as low as 10 to 15 degreeC. In contrast, the temperatures of the housewife 416 and the infant 417are the highest. In particular, the upper body temperatures of thehousewife 416 and the infant 417 range from 26 to 30 degree C. Byturning the infrared ray sensor 410 in the horizontal direction in thismanner, the temperature information relating to each part of the room,for example, can be obtained.

The indoor unit 100 according to Embodiment 1, then controls the airvolumes of each fans 20, the orientation of the vertical wind directioncontrol vane 70, and the orientation of the horizontal wind directioncontrol vane 80 on the basis of the temperature information of each partof the room obtained by the infrared ray sensor 410. More specifically,the control device 281 provided in the indoor unit 100 is provided withan input unit, a CPU, a memory, and an output unit. In addition, the CPUincludes an indoor state gauging unit, a target area determining unit,an area wind direction control unit integrated in the interior thereof.The control device 281 divides the floor surface area in the room into aplurality of area blocks, and replaces each coordinate points of theheat image data acquired by the infrared ray sensor 410 with theseplurality of area blocks. Accordingly, the area blocks in the room wherea person is present can be recognized with high degree of accuracy.

FIG. 10 shows an example in which the indoor unit according toEmbodiment 1 divides the floor surface area in the room into theplurality of area blocks.

For example, the control device 281 of the indoor unit 100 divides thefloor surface area in the room into fifteen area blocks, namely A1 toE3. Then, the control device 281 controls the orientations of thevertical wind direction control vane 70 and the horizontal winddirection control vane 80 on the basis of the heat source data acquiredfrom the infrared ray sensor 410. The control device 281 also controlsthe air volumes of each fans 20 on the basis of the heat source dataacquired from the infrared ray sensor 410.

For example, when the airflow blown out from the blow-out port 3 needsto be distributed far, the rotation speed of all the fans 20 areincreased (the air volumes of all the fans 20 are increased), and theair volume blown out from the blow-out port 3 is increased. Also, forexample, when the airflow blown out from the blow-out port 3 needs to bedistributed very close to the indoor unit 100, the revolution speed ofall the fans 20 are decreased (the air volumes of all the fans 20 aredecreased), and the air volume blown out from the blow-out port 3 isdecreased.

Also, for example, there are instances when intensive air-conditioningis desired in an area block where a person is present even when the roomtemperature is close to its set temperature. In such a case, the airvolume (that is, the rotation speed) of the fan 20 which generates anairflow reaching a place where the intensive air-conditioning is desired(the area block where a person is present) is increased. At this time,the remaining fans 20 may be operated at a low rotation speed or may bestopped. By controlling the air volumes of each fans 20 in this manner,the airflow can be distributed intensively to an area block where aperson is present although the air volume of the entire airflow blownout from the blow-out port 3 of the indoor unit 100 is small.Accordingly, the temperature environment in the area block where aperson is present can be further maintained, and comfortable andenergy-saving operation of the indoor unit 100 can be realized.

Also, for example, there may be some who want to keep away from theairflow blown out from the blow-out port 3 of the indoor unit 100. Inthis manner, if there is an area where avoidance of the airflow blownout from the blow-out port 3 of the indoor unit 100 is desired, the airvolume (that is, the rotation speed) of the fan 20 which generates theairflow reaching the place where the avoidance of the airflow blown outfrom the blow-out port 3 is desired is decreased. By controlling the airvolumes of each fans 20 in this manner, the air conditioning in the roomcan be performed while restraining the airflow blown out from theblow-out port 3 from reaching the corresponding place. Accordingly, thecomfortable and energy-saving operation of the indoor unit 100 can berealized while maintaining the environment of the place where avoidanceof the airflow blown out from the blow-out port 3 of the indoor unit 100is desired.

When controlling the air volumes of each fans 20 individually asdescribed above, the fan 20 to generate the airflow reaching the “placewhere intensive air-conditioning is desired” or the “place whereavoidance of the airflow blown out from the blow-out port 3 is desired”may be assigned to the fan 20 which is closest to the correspondingplace. For example, when the area block E3 shown in FIG. 10 correspondsto the place as described above, the fan 20 which is to generate anairflow reaching the area block E3 may be assigned to the fan 20C (seeFIG. 3). By selecting the fan 20 in this manner, the overall airflowblown out from the blow-out port 3 of the indoor unit 100 can bedistributed to the substantially center portion in the room, so thatfurther energy-saving operation of the indoor unit 100 can be realized.

(Drain Pan)

FIG. 15 is a perspective view of the indoor unit according to Embodiment1 of the invention when viewed from the front right side. FIG. 16 is aperspective view of the same indoor unit when viewed from the back rightside. FIG. 17 is a perspective view of the same indoor unit when viewedfrom the front left side. FIG. 18 is a perspective view illustrating adrain pan according to Embodiment 1 of the invention. In order tofacilitate understanding of the shape of the drain pan, the right sideof the indoor unit 100 is shown in cross section in FIG. 15 and FIG. 16,and the left side of the indoor unit 100 is shown in cross section inFIG. 17.

Provided below a lower end portion of the front side heat exchanger 51(a front side end portion of the front side heat exchanger 51) is afront side drain pan 110. Provided below a lower end portion of the backside heat exchanger 55 (a back side end portion of the back side heatexchanger 55) is a back side drain pan 115. In Embodiment 1, the backside drain pan 115 and a back side portion 1 b of the casing 1 areintegrally formed. In the back side drain pan 115, connecting ports 116to which a drain hose 117 is connected are provided on both a left sideend portion and a right side end portion. It is not necessary to connectthe drain hose 117 to both of the connecting ports 116, and the drainhose 117 may be connected to one of the connecting ports 116. Forexample, when drawing of the drain hose 117 to the right side of theindoor unit 100 is desired at the time of installation of the indoorunit 100, the drain hose 117 is connected to the connecting port 116provided on the right side end portion of the back side drain pan 115,and the connecting port 116 provided on the left side end portion of theback side drain pan 115 may be closed with a rubber cap or the like.

The front side drain pan 110 is arranged at a position higher than theback side drain pan 115. Provided between the front side drain pan 110and the back side drain pan 115 on both of the left side end portion andthe right side end portion are drain channels 111 which correspond todrain flow channels. The drain channels 111 are each connected at an endportion on the front side thereof to the front side drain pan 110, andare provided so as to incline downward from the front side drain pan 110toward the back side drain pan 115. Also, formed at end portions of thedrain channels 111 on the back side are tongue portions 111 a. The endportions of the drain channels 111 on the back side are arranged so asto extend over an upper surface of the back side drain pan 115.

When the indoor air is cooled by the heat exchangers 50 at the time ofcooling operation, dew condensation forms on the heat exchangers 50.Then, dew on the front side heat exchanger 51 drops from the lower endportion of the front side heat exchanger 51, and is collected by thefront side drain pan 110. Dew on the back side heat exchanger 55 dropsfrom the lower end portion of the back side heat exchanger 55, and iscollected by the back side drain pan 115.

Since the front side drain pan 110 is provided at a position higher thanthe back side drain pan 115 in Embodiment 1, the drain water collectedby the front side drain pan 110 flows through the drain channel 111toward the back side drain pan 115. Then, the drain water drops downfrom the tongue portion 111 a of the drain channel 111 to the back sidedrain pan 115, and is collected by the back side drain pan 115. Thedrain water collected by the back side drain pan 115 passes through thedrain hose 117, and is drained to the outside of the casing 1 (theindoor unit 100).

As in Embodiment 1, by providing the front side drain pan 110 at aposition higher than the back side drain pan 115, the drain watercollected by both of the drain pans can be gathered in the back sidedrain pan 115 (the drain pan arranged on the backmost side of the casing1). Therefore, by providing the connecting port 116 of the drain hose117 in the back side drain pan 115, the drain water collected in thefront side drain pan 110 and the back side drain pan 115 can be drainedto the outside of the casing 1. When performing maintenance (cleaning ofthe heat exchangers 50 and the like) of the indoor unit 100 by openingthe front side portion or the like of the casing 1, there is, therefore,no need to detach and attach the drain pan having the drain hose 117connected thereto, thus workability such as maintenance is improved.

Since the drain channels 111 are provided on both the left side endportion and the right side end portion, even when the indoor unit 100 isinstalled in an inclined state, the drain water collected in the frontside drain pan 110 can be guided reliably to the back side drain pan115. Since the connecting ports to which the drain hoses 117 are to beconnected are provided on both the left side end portion and the rightside end portion, the drawing direction of the hose can be selectedaccording to the conditions of the indoor unit 100 in installation, sothat workability when installing the indoor unit 100 is improved. Also,since the drain channels 111 are provided so as to extend over the backside drain pan 115 (that is, since a connecting mechanism is notnecessary between the drain channel 111 and the back side drain pan115), attachment and detachment of the front side drain pan 110 isfacilitated, and hence maintainability is further improved.

It is also possible to connect the back side end of the drain channels111 to the back side drain pan 115 and arrange the drain channels 111 sothat the front side drain pan 110 extends over the drain channels 111.In this configuration as well, the same effects as the configuration inwhich the drain channels 111 are arranged so as to extend over the backside drain pan 115 are achieved. The front side drain pan 110 does notnecessarily have to be provided at a higher position than the back sidedrain pan 115, and the drain water collected in both drain pans can bedrained from the drain hose connected to the back side drain pan 115even when the front side drain pan 110 and the back side drain pan 115are provided at the same level.

(Nozzle)

The indoor unit 100 according to Embodiment 1 is configured in such amanner that an opening length d1 of a nozzle 6 on the suction side (athrottle length d1 between the drain pans defined by a portion betweenthe front side drain pan 110 and the back side drain pan 115) is definedto be larger than an opening length d2 (the length of the blow-out port3) of the nozzle 6 on the blow-out side. In other words, the nozzle 6 ofthe indoor unit 100 has opening lengths which satisfy d1>d2.

The reason why the nozzle 6 is configured to have opening lengths ofd1>d2 is as follows. Since the value d2 affects the distributiondistance of the airflow, which is one of basic functions of the indoorunit, the opening length d2 of the indoor unit 100 according toEmbodiment 1 is assumed to be a comparable length with the blow-out portof the conventional indoor unit in the description given below.

By setting the dimensions of the nozzle 6 in the vertical cross sectionto be d1>d2, the air path is widened, and an angle A of the heatexchanger 50 arranged on the upstream side (the angle formed between thefront side heat exchanger 51 an the back side heat exchanger 55 on thedownstream side of the heat exchanger 50) can be widened. Therefore, thewind velocity distribution generated in the heat exchanger 50 isreduced, and the air path of the downstream side of the heat exchanger50 can be widened, whereby reduction of pressure loss in the entireindoor unit 100 can be achieved. In addition, the deviation of the windvelocity distribution generated in the vicinity of the inlet portion ofthe nozzle 6 can be unified and guided to the blow-out port by theeffect of flow contraction.

For example, when the deviation of the wind velocity distributiongenerated in the vicinity of the inlet portion of the nozzle 6 (forexample, a flow deviated toward the back side) is reflected directly inthe deviation of the wind velocity distribution at the blow-out port 3.In other words, when d1=d2, air is blown out from the blow-out port 3still having the deviation in the wind velocity distribution. When d1<d2is satisfied, for example, the contraction flow loss is increased whenairflows passed through the front side heat exchanger 51 and the backside heat exchanger 55 merge in the vicinity of the inlet portion of thenozzle 6. Therefore, when d1<d2 is satisfied, a loss corresponding tothe contraction flow loss is generated unless otherwise a diffusioneffect at the blow-out port 3 cannot be obtained.

(ANC)

In the indoor unit 100 according to Embodiment 1, an active silencingmechanism is provided as shown in FIG. 1.

More specifically, the silencing mechanism of the indoor unit 100according to Embodiment 1 includes a noise detection microphone 161, acontrol speaker 181, a silencing effect detection microphone 191, and asignal processing device 201. The noise detection microphone 161 is anoise detection device configured to detect an operation sound (noise)of the indoor unit 100 including a blast sound of the fan 20. The noisedetection microphone 161 is arranged between the fan 20 and the heatexchanger 50. In Embodiment 1, the noise detection microphone 161 isprovided on the front surface portion in the casing 1. The controlspeaker 181 is a control sound output device configured to output acontrol sound with respect to the noise. The control speaker 181 isarranged below the noise detection microphone 161 and above the heatexchanger 50. In Embodiment 1, the control speaker 181 is provided onthe front surface portion in the casing 1 so as to face the center ofthe air path. The silencing effect detection microphone 191 is asilencing effect detection device configured to detect the silencingeffect using the control sound. The silencing effect detectionmicrophone 191, being intended to detect a noise coming from theblow-out port 3, is provided in the vicinity of the blow-out port 3. Thesilencing effect detection microphone 191 is attached at a positionavoiding the airflow so as not to be exposed to the air coming out fromthe blow-out port 3. The signal processing device 201 is a control soundgenerating device configured to cause the control speaker 181 to outputthe control sound on the basis of the results of detection by the noisedetection microphone 161 and the silencing effect detection microphone191. The signal processing device 201 is housed, for example, in thecontrol device 281.

FIG. 20 is a configuration drawing illustrating a signal processingdevice according to Embodiment 1 of the invention. Electric signalssupplied from the noise detection microphone 161 and the silencingeffect detection microphone 191 are amplified by a microphone amplifier151, and are converted from analogue signals to digital signals by anA/D converter 152. The converted digital signals are input to an FIRfilter 158 and an LMS algorithm 159. In the FIR filter 158, a controlsignal, which is corrected to cause a noise with the same amplitude asand an opposite phase from the detected noise by the noise detectionmicrophone 161 when the noise reaches a position where the silencingeffect detection microphone 191 is installed, and is converted from adigital signal to an analogue signal by an D/A converter 154, then isamplified by an amplifier 155, and then is emitted as the control soundfrom the control speaker 181.

In a case where the air-conditioning apparatus is in cooling operation,for example, as shown in FIG. 19, the temperature in an area B betweenthe heat exchanger 50 and the blow-out port 3 is lowered due to coolair, thereby causing dew condensation to appear as water droplets fromwater vapor in the air. Therefore, in the indoor unit 100, a water trapor the like (not shown) is attached in the vicinity of the blow-out port3 for preventing the water droplets from coming out from the blow-outport 3. The area where the noise detection microphone 161 and thecontrol speaker 181 are arranged, which is on the upstream side of theheat exchanger 50 is not subjected to dew condensation, because it islocated on the upstream side of the area to be cooled by cool air.

Subsequently, a method of restraining an operating sound of the indoorunit 100 will be described. The operating sound (noise) including theblast sound of the fan 20 in the indoor unit 100 that is detected by thenoise detection microphone 161 attached between the fan 20 and the heatexchanger 50 is converted into a digital signal via the microphoneamplifier 151 and the ND converter 152, and is supplied to the FIRfilter 158 and the LMS algorithm 159.

A tap coefficient of the FIR filter 158 is updated sequentially by theLMS algorithm 159. The tap coefficient is updated by the LMS algorithm159 according to an expression 1(h(n+1)=h(n)+2μe(n)×(n)), and is updatedto an optimal tap coefficient so as to cause an error signal e toapproach zero.

In the expression shown above, h is a tap coefficient of the filter, eis the error signal, x is a filter input signal, and μ is a step sizeparameter, and the step size parameter μ is used for controlling theupdate amount of the filter coefficient at every sampling.

In this manner, the digital signal passed through the FIR filter 158whose tap coefficient is updated by the LMS algorithm 159 is convertedinto an analogue signal by the D/A converter 154, is amplified by theamplifier 155, and is released into the air path in the indoor unit 100as the control sound from the control speaker 181 attached between thefan 20 and the heat exchanger 50.

And the silencing effect detection microphone 191, attached to a lowerend of the indoor unit 100 on the outer wall of the blow-out port 3 soas to avoid wind blown out from the blow-out port 3, detects a soundwhich has been propagated from the fan 20 to the air path coming outfrom the blow-out port, the sound after having been interfered by thecontrol sound released from the control speaker 181.

Since the sound detected by the silencing effect detection microphone191 is input to the error signal of the LMS algorithm 159 describedabove, the tap coefficient of the FIR filter 158 is updated so as tocause the sound after the interference to approach zero. Consequently,the noise in the vicinity of the blow-out port 3 can be restrained bythe control sound having passed through the FIR filter 158.

In this manner, in the indoor unit 100 to which an active silencingmethod is applied, the noise detection microphone 161 and the controlspeaker 181 are arranged between the fan 20 and the heat exchanger 50,and the silencing effect detection microphone 191 is attached to aposition avoiding the airflow from the blow-out port 3. Therefore, sinceit is not necessary to attach members required for active silencing toarea B which is subjected to dew condensation, water droplets droppingon the control speaker 181, the noise detection microphone 161, and thesilencing effect detection microphone 191 is prevented, and hencedeterioration of silencing capabilities or defects of the speaker or themicrophone can be prevented.

The positions where the noise detection microphone 161, the controlspeaker 181, and the silencing effect detection microphone 191 areattached shown in Embodiment 1 are only examples. For example, as shownin FIG. 21, the silencing effect detection microphone 191 may bearranged between the fan 20 and the heat exchanger 50 together with thenoise detection microphone 161 and the control speaker 181. Although themicrophone is exemplified as detecting means for detecting the noise orthe silencing effect after having cancelled the noise using the controlsound, it may be an acceleration sensor or the like for sensingvibrations of the casing. Alternatively, it is also possible tounderstand the sound as turbulence of air current, and detect the noiseor the silencing effect after having cancelled the noise by the controlsound as turbulence of the air current, In other words, a flow velocitysensor which detects the air current or a hot-wire probe may be used asthe detecting means for detecting the noise or the silencing effectafter having cancelled the noise using the control sound. It is alsopossible to detect the air current by increasing a gain of themicrophone.

Although the FIR filter 158 and the LMS algorithm 159 are employed inthe signal processing device 201 in Embodiment 1, any adaptive signalprocessing circuit may be employed as long as it causes the sounddetected by the silencing effect detection microphone 191 to approachzero, and also may be one in which a filtered-X algorithm generally usedin the active silencing method is applicable. In addition, the signalprocessing device 201 may be configured to generate the control signalusing a fixed tap coefficient instead of employing adaptive signalprocessing. And further, the signal processing device 201 may be ananalogue signal processing circuit instead of the digital signalprocessing circuit.

In addition, in Embodiment 1, the heat exchanger 50 disposed to cool airwhich forms due condensation has been described, but the invention canbe applied also to a case where the heat exchanger 50 of a level whichdoes not cause dew condensation is arranged, and has effects to preventdeterioration of performances of the noise detection microphone 161, thecontrol speaker 181, the silencing effect detection microphone 191, andthe like without considering the presence or absence of occurrence ofdue condensation due to the heat exchanger 50.

Embodiment 2

(Dividing Vane into Plurality of Parts)

When controlling the vertical wind direction control vane 70, thehorizontal wind direction control vane 80, and the air volume of eachfans 20 on the basis of the results of detection by the infrared raysensor 410, dividing the vertical wind direction control vane 70 and thehorizontal wind direction control vane 80 into a plurality of parts andcontrolling the same individually is recommended. Accordingly, comfortcan further be improved. In Embodiment 2, items not specificallydescribed are the same as those in Embodiment 1, and the same numbersreference the same functions and configurations in the description.

FIG. 11 is a front cross-sectional view illustrating the indoor unitaccording to Embodiment 2 of the invention. FIG. 12 is a perspectiveview illustrating the same indoor unit. FIG. 11 is a frontcross-sectional view taken along the substantially center portions ofthe fans 20.

In the indoor unit 100 according to Embodiment 2, the vertical winddirection control vane 70 and the horizontal wind direction control vane80 are divided into a plurality of parts (in FIG. 11 and FIG. 12, thevertical wind direction control vane 70 and the horizontal winddirection control vane 80 are each divided into two parts).

More specifically, the horizontal wind direction control vane 80 isdivided into a horizontal wind direction control vane 80 a arranged onthe left side of the casing 1 and a horizontal wind direction controlvane 80 b arranged on the right side of the casing 1. The horizontalwind direction control vane 80 a is coupled to a motor 81 a, such as astepping motor, via a link rod 82 a. The horizontal wind directioncontrol vane 80 b is coupled to a motor 81 b, such as a stepping motor,via a link rod 82 b. By the motor 81 a and the motor 81 b drivenaccording to the number of steps commanded by the control device 281,the orientations (angles) of the horizontal wind direction control vane80 a and the horizontal wind direction control vane 80 b are changed andthe direction of airflow blown from the blow-out port 3 can becontrolled in the horizontal direction. The orientations (angles) of thehorizontal wind direction control vane 80 a and the horizontal winddirection control vane 80 b can each be changed individually.

The vertical wind direction control vane 70 is divided into a verticalwind direction control vane 70 a arranged on the left side of the casing1 and a vertical wind direction control vane 70 b arranged on the rightside of the casing 1. The vertical wind direction control vane 70 a andthe vertical wind direction control vane 70 b are each coupled to motors(not shown) such as stepping motors. By these motors driven according tothe number of steps commanded by the control device 281, theorientations (angles) of the vertical wind direction control vane 70 aand the vertical wind direction control vane 70 b are changed and thedirection of airflow blown from the blow-out port 3 can be controlled inthe vertical direction. The orientations (angles) of the vertical winddirection control vane 70 a and the vertical wind direction control vane70 b can each be changed individually.

In other words, the indoor unit 100 according to Embodiment 2 is capableof distributing airflows having different air volumes simultaneously totwo different places in a room. Therefore, the air volumes in the twodifferent places in the room can be controlled individually in such amanner that the air volume of the airflow to be distributed to thecorresponding place may be increased if intensive distribution of theairflow is desired, and the air volume of the airflow to be distributedto the corresponding place may be decreased if avoidance of the airflowis desired. Therefore, air-conditioning in the room while maintainingthe environments at two different places simultaneously is enabled.

For example, assume that two people are present in two separate areablocks in a room. Then, if intensive air-conditioning of these two areablocks is desired, the air volumes (that is, the rotation speed) of thefans 20 which generate the airflows reaching these two area blocks areincreased. The remaining fan 20 is operated with a low air volume or isstopped. By controlling the air volumes of each fans 20 in this manner,the airflow can be distributed intensively to the area block wherepeople are present although the air volume of the overall airflow blownout from the blow-out port 3 of the indoor unit 100 is decreased.Accordingly, the temperature environment in the area block where peopleare present can be further maintained, and comfortable and energy-savingoperation of the indoor unit 100 can be realized.

Also, for example, assume that two people are present in two separatearea blocks in a room, and a set temperature is reached in one of thearea blocks but not in the remaining one area block. In such a case, theair volume (that is, the rotation speed) of the fan 20 which generatesan airflow reaching a place where the intensive air-conditioning isdesired (the area block where the set temperature is not reached) isincreased. The air volume (that is, the rotation speed) of the fan 20which generates the airflow reaching the area block in which the settemperature is reached is decreased to a low air volume. The remainingfan 20 is operated with a low air volume or is stopped. By controllingthe air volumes of each fans 20 in this manner, the airflow can bedistributed intensively to a place where the intensive air-conditioningis desired (the area blocks where the set temperature is not reached),and the airflow with a small air volume can be distributed also to thearea block where the set temperature is reached.

In other words, with the indoor unit 100 according to Embodiment 2 inwhich the vertical wind direction control vane 70 and the horizontalwind direction control vane 80 are divided into parts, more comfortableand energy-saving operation than that of the indoor unit 100 accordingto Embodiment 1 can be realized.

Embodiment 3

(Dividing Vane into Number of Parts as Same as the Number of Fans)

By increasing the number of divisions of the vertical wind directioncontrol vane 70 and the horizontal wind direction control vane 80, thecomfort can further be improved. Also, by employing the number ofdivisions of the vertical wind direction control vane 70 and thehorizontal wind direction control vane 80 as many as the number of thefans 20, the comfort can further be improved. In Embodiment 3, items notspecifically described are the same as those in Embodiment 1 andEmbodiment 2, and the same numbers reference the same functions andconfigurations in the description.

FIG. 13 is a front cross-sectional view illustrating the indoor unitaccording to Embodiment 3 of the invention. FIG. 14 is a perspectiveview illustrating the same indoor unit. FIG. 13 is a frontcross-sectional view taken along the substantially center portions ofthe fans 20. The indoor unit 100 shown in FIG. 13 and FIG. 14 show theindoor unit 100 having three fans 20 (fans 20A to 20C).

In the indoor unit 100 according to Embodiment 3, the vertical winddirection control vane 70 and the horizontal wind direction control vane80 are divided into parts as many as the number of the fans 20. Sincethe indoor unit 100 according to Embodiment 3 includes three fans 20(fans 20A to 20C), the vertical wind direction control vane 70 and thehorizontal wind direction control vane 80 are each divided into threeparts.

More specifically, the horizontal wind direction control vane 80 isdivided into the horizontal wind direction control vane 80 a arranged onthe left side of the casing 1, the horizontal wind direction controlvane 80 b arranged at the center portion of the casing 1, and ahorizontal wind direction control vane 80 c arranged on the right sideof the casing 1. The horizontal wind direction control vane 80 a iscoupled to the motor 81 a, such as the stepping motor, via the link rod82 a. The horizontal wind direction control vane 80 b is coupled to themotor 81 b, such as the stepping motor, via the link rod 82 b. Thehorizontal wind direction control vane 80 c is coupled to a motor 81 c,such as a stepping motor, via a link rod 82 c. By the motor 81 a to themotor 81 c each driven according to the number of steps commanded by thecontrol device 281, the orientations (angles) of the horizontal winddirection control vane 80 a to the horizontal wind direction controlvane 80 c are changed and the direction of airflow blown from theblow-out port 3 can be controlled in the horizontal direction. Theorientations (angles) of the horizontal wind direction control vane 80 ato the horizontal wind direction control vane 80 c can each be changedindividually.

The vertical wind direction control vane 70 is divided into the verticalwind direction control vane 70 a arranged on the left side of the casing1, the vertical wind direction control vane 70 b arranged at the centerportion of the casing 1, and a vertical wind direction control vane 70 carranged on the right side of the casing 1. The vertical wind directioncontrol vane 70 a to the vertical wind direction control vane 70 c areeach coupled to motors (not shown) such as stepping motors. By thesemotors driven according to the number of steps commanded by the controldevice 281, the orientations (angles) of the vertical wind directioncontrol vane 70 a to the vertical wind direction control vane 70 c arechanged and the direction of airflow blown from the blow-out port 3 canbe controlled in the vertical direction. The orientations (angles) ofthe vertical wind direction control vane 70 a to the vertical winddirection control vane 70 c can each be changed individually.

In other words, the indoor unit 100 according to Embodiment 3 is capableof distributing airflows having different air volumes simultaneously tothree different places in a room. Therefore, the air volumes in thethree different places in the room can be controlled individually insuch a manner that the air volume of the airflow to be distributed tothe corresponding place may be increased if intensive distribution ofthe airflows is desired, and the air volume of the airflow to bedistributed to the corresponding place may be decreased if avoidance ofthe airflow is desired. Therefore, air-conditioning in the room whilemaintaining the environments at the three different placessimultaneously is enabled.

For example, assume that three people are present in three separate areablocks in a room, and a set temperature is reached in one of the areablocks but not in the remaining two area blocks. In such a case, the airvolumes (that is, the rotation speeds) of the fans 20 which generateairflows reaching places where the intensive air-conditioning is desired(the two area blocks where the set temperature is not reached) are eachincreased. The air volume (that is, the rotation speed) of the fan 20which generates the airflow reaching the area block in which the settemperature is reached is decreased to a low air volume. By controllingthe air volumes of each fans 20 in this manner, the airflows can bedistributed intensively to places where the intensive air-conditioningis desired (the two area blocks where the set temperature is notreached), and the airflow with a small air volume can be distributedalso to the area block where the set temperature is reached.Accordingly, the temperature environment of the area block where the settemperature is reached can be maintained while actively air-conditioningthe places where the intensive air-conditioning are desired (the twoarea blocks where the set temperature is not yet reached).

In other words, with the indoor unit 100 according to Embodiment 3 inwhich the number of divisions of the vertical wind direction controlvane 70 and the horizontal wind direction control vane 80 is larger thanthat in Embodiment 2, further comfortable and energy-saving operationthan that of the indoor unit 100 according to Embodiment 2 can berealized.

Also, in Embodiment 3, since the numbers of divisions of the verticalwind direction control vane 70 and the horizontal wind direction controlvane 80 are set to be the same as the number of the fans 20, the comfortcan further be improved. In other words, as shown in FIG. 13 and FIG.14, the direction of the airflow generated by the fan 20A is controlledby the vertical wind direction control vane 70 a and the horizontal winddirection control vane 80 a. The direction of the airflow generated bythe fan 20B is controlled by the vertical wind direction control vane 70b and the horizontal wind direction control vane 80 b. The direction ofthe airflow generated by the fan 20C is controlled by the vertical winddirection control vane 70 c and the horizontal wind direction controlvane 80 c. Therefore, the airflows controlled respectively by thevertical wind direction control vane 70 and the horizontal winddirection control vane 80 are not the airflows generated by theplurality of fans 20, but an airflow generated by a single fan 20.Therefore, the air volume of the airflow to be distributed to a placewhere intensive control of the air volume is desired can be adjustedwith high degree of accuracy, and further comfortable and energy-savingoperation than the indoor unit 100 in which the numbers of divisions ofthe vertical wind direction control vane 70 and the horizontal winddirection control vane 80 and the number of the fans 20 are different(for example, the indoor units 100 according to Embodiment 1 andEmbodiment 2) can be realized.

REFERENCE SIGNS LIST

-   1 casing, 1 b back side portion, 2 suction port, 3 blow-out port, 5    bell mouth, 5 a upper portion, 5 b center portion, 5 c lower    portion, 6 nozzle, filter, 15 finger guard, 16 motor stay, 17 fixed    member, 18 supporting member, 20 fan, 20 a axis of rotation, 21    boss, 30 fan motor, 50 heat exchanger, 50 a line of symmetry, 51    front side heat exchanger, 55 back side heat exchanger, 56 fin, 57    heat-transfer tube, vertical wind direction control vane, 70 a    vertical wind direction control vane, 70 b vertical wind direction    control vane, 70 c vertical wind direction control vane, 80    horizontal wind direction control vane, 80 a horizontal wind    direction control vane, 80 b horizontal wind direction control vane,    80 c horizontal wind direction control vane, 81 motor, 81 a motor,    81 b motor, 81 c motor, link rod, 82 a link rod, 82 b link rod, 82 c    link rod, 90 partitioning panel, 100 indoor unit, 110 front side    drain pan, 111 drain channel, 111 a tongue portion, 115 back side    drain pan, 116 connecting port, 117 drain hose, 151 microphone    amplifier, 152 ND converter, 154 D/A converter, 155 amplifier, 158    FIR filter, 159 LMS algorithm, 161 noise detection microphone, 181    control speaker, 191 silencing effect detection microphone, 201    signal processing device, 281 control device, 410 infrared ray    sensor, 411 metallic container, 412 light distribution view angle,    413 housing, 414 motor, 415 mounting portion, 416 housewife, 417    infant, 418 window

1. An indoor unit of an air-conditioning apparatus comprising: a casinghaving a suction port formed in an upper portion and a blow-out portformed on a lower side of a front surface portion; a plurality ofaxial-flow or mixed-flow fans provided in parallel on the downstreamside of the suction port in the casing; a heat exchanger provided on thedownstream side of the fans and on the upstream side of the blow-outport in the casing and configured to exchange heat between air blown outfrom the fans and a refrigerant; a horizontal wind direction controlvane provided at the blow-out port and configured to control ahorizontal direction of an airflow blown out from the blow-out port; avertical wind direction control vane provided at the blow-out port andconfigured to control a vertical direction of the airflow blown out fromthe blow-out port; and a human detection sensor configured to detect aposition of a person present in a room, wherein air volume, anorientation of the horizontal wind direction control vane, and anorientation of the vertical wind direction control vane of the fans areeach controlled according to detected results of the human detectionsensor.
 2. The indoor unit of the air-conditioning apparatus of claim 1,wherein the horizontal wind direction control vane is divided into aplurality of horizontal wind direction control vanes, the vertical winddirection control vane is divided into the same number of vanes as thehorizontal wind direction control vane, and the divided horizontal winddirection control vanes and the vertical wind direction control vanesare controlled in terms of orientation individually.
 3. The indoor unitof the air-conditioning apparatus of claim 2, wherein the horizontalwind direction control vane and the vertical wind direction control vaneare divided into the same number of parts as the number of the fans. 4.The indoor unit of the air-conditioning apparatus of claim 1, whereinwhen there is a place where intensive air-conditioning is desired in aroom, the air volume of a fan closest to the corresponding place isincreased.
 5. The indoor unit of the air-conditioning apparatus of claim1, wherein when there is a place where avoidance of the airflow blownout from the blow-out port is desired in the room, the air volume of afan closest to the corresponding place is decreased.
 6. Anair-conditioning apparatus comprising the indoor unit of theair-conditioning apparatus of claim 1.